Expert Commentary

Dynamic public opinion: Communication effects over time

2010 study in the American Political Science Review on the variables that can affect public views on issues over time.

Scholars from Northwestern University set out to study an underappreciated aspect of public opinion and communications: how the sequence and timing of messages from electoral and policy campaigns can shape views over longer intervals of time. Typically, as the scholars point out, experimental research has focused on the short-term effects of a given message on the public and has found that two competing, simultaneous messages can cancel one another out.

Their 2010 study published in the American Political Science Review, “Dynamic Public Opinion: Communication Effects over Time,” uses two experiments to test how citizens respond to different sequences of messages and how stable their attitudes prove to be. The first experiment asked 1,302 respondents to give their views on the U.S. Patriot Act over a 10-day period; the second asked 749 participants about an urban growth policy over a 21-day period.

The study’s authors focus on the key idea of “framing effects,” which happen “when a communication changes people’s attitudes toward an object by changing the relative weights they give to competing considerations about the object.” (A concrete example, the scholars explain, would be having a person read a persuasive editorial about free speech before surveying his opinion about the right of hate groups to speak their mind in public.) Framing can thus distort temporarily what an individual may actually believe at a deeper level on an issue.

The study’s chief findings include:

  • The timing of messages received by individuals proves crucial: “When competing messages are received simultaneously, individuals can weigh the relative merits of opposing arguments. But when people receive competing messages across different periods rather than concurrently, the accessibility of previous arguments tends to decay over time.”
  • In sum, this means that “individuals typically give greater weight to the more immediate cues contained in the most recent message. Democratic competition thus may reduce or eliminate framing effects only when people are presented with opposing frames at the same time.”
  • Although framing effects decay on average, there was significant individual variation, and some experiment participants appeared to hold to attitudes more strongly over time and resist contrary information.
  • The results suggest that the “persistence of framing effects may be related to contextual factors such as the salience of the issue [how prominent an issue already is, and therefore how much public opinions may already be shaped], the duration of time between messages, or the particular combination of frames received.”

Overall, the study demonstrates that “most individuals were shown to be vulnerable to the vagaries of timing and the framing of communications.” The authors conclude that the evidence suggests successful campaigns to win over public opinion should seek to communicate early (to shape initial attitudes), often (to compete with competing frames) and late (given the decay of framing effects).

Tags: communication

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